Melnikov Anatoly R, Davydova Maria P, Sherin Peter S, Korolev Valeri V, Stepanov Alexander A, Kalneus Evgeny V, Benassi Enrico, Vasilevsky Sergei F, Stass Dmitri V
Institute of Chemical Kinetics and Combustion SB RAS , 3, Institutskaya Str., 630090 Novosibirsk, Russian Federation.
Novosibirsk State University , 2, Pirogova Str., 630090 Novosibirsk, Russian Federation.
J Phys Chem A. 2018 Feb 8;122(5):1235-1252. doi: 10.1021/acs.jpca.7b11634. Epub 2018 Jan 24.
Customizable and technology-friendly functional materials are one of the mainstays of emerging organic electronics and optoelectronics. We show that recombination exciplexes of simple substituted diphenylacetylenes with tertiary amines can be a convenient source of tunable deep-blue emission with possible applications in organic electroluminescent systems. The optically inaccessible exciplexes were produced via recombination of radiation-generated radical ion pairs in alkane solution, which mimics charge transport and recombination in the active layer of practical organic light-emitting diodes in a simple solution-based experiment. Despite varying and rather poor intrinsic emission properties, diphenylacetylene and its prototypical methoxy (donor) or trifluoromethyl (acceptor) monosubstituted derivatives readily form recombination exciplexes with N,N-dimethylaniline and other tertiary amines that produce emission with maxima ranging from 385 to 435 nm. The position of emission band maximum linearly correlates with readily calculated gas-phase electron affinity of the corresponding diphenylacetylene, which can be used for fast computational prescreening of the candidate molecules, and various substituted diphenylacetylenes can be synthesized via relatively simple and universal cross-coupling reactions of Sonogashira and Castro. Together, the simple solution-based experiment, computationally cheap prescreening method, and universal synthetic strategy may open a very broad and chemically convenient class of compounds to obtain OLEDs and OLED-based multifunctional devices with tunable emission spectrum and high conversion efficiency that has yet not been seriously considered for these purposes.
可定制且对技术友好的功能材料是新兴有机电子学和光电子学的支柱之一。我们表明，简单取代的二苯乙炔与叔胺的复合激基复合物可以成为可调谐深蓝色发射的便捷来源，在有机电致发光系统中可能具有应用价值。在烷烃溶液中，通过辐射产生的自由基离子对的复合产生了光学上难以接近的激基复合物，这在一个简单的基于溶液的实验中模拟了实际有机发光二极管活性层中的电荷传输和复合。尽管二苯乙炔及其典型的甲氧基（供体）或三氟甲基（受体）单取代衍生物具有不同且相当差的固有发射特性，但它们很容易与N,N-二甲基苯胺和其他叔胺形成复合激基复合物，产生最大发射波长在385至435nm范围内的发射。发射带最大值的位置与相应二苯乙炔易于计算的气相电子亲和力呈线性相关，这可用于对候选分子进行快速计算预筛选，并且各种取代的二苯乙炔可以通过Sonogashira和Castro相对简单且通用的交叉偶联反应合成。总之，基于溶液的简单实验、计算成本低的预筛选方法和通用的合成策略可能会开辟一类非常广泛且化学上便利的化合物，以获得具有可调发射光谱和高转换效率的有机发光二极管及基于有机发光二极管的多功能器件，而这些目的尚未被认真考虑过。
